already on the front line. this is easy co., a band of brothers. for most of them, it is the second or third tour of duty here. the mission is to drive the taliban from these mountains. we are heading into a village, about 12 miles from the pakistani border. they will not be able to stop the insurgents coming across the border, but they're hoping that with more regular patrol as a result from the extra troops, they can deter them, and having the extra troops will make locals here feel safer. the surge has brought sergeant caldwell to afghanistan for a third time. >> from when i was here the first time back in 2002, the same guys we fought against, now, they have been fighting with the u.s. or coalition forces for almost 10 years now.